Ribbon feed mechanism in selective printing machines



Feb. 4, 1958 L. M. LLORENS 2,821,918

RIBBON FEED MECHANISM IN SELECTIVE PRINTING MACHINES 2 Shets-Sheet 1 Original Filed July 29, 1950 AT TORNEfS.

Feb. 4, 1958 L. M. LLORENS RIBBON FEED MECHANISM IN SELECTIVE PRINTING MACHINES 2 Sheets-Sheet 2 Original Filed July 29, 1950 INVENTOR.

LOUIS M. LLORENS ATTORNEYS United States Patent C RIBBON FEED MECHANISM IN SELECTIVE PRINTING MACHINES Louis M. Llorens, Groton, N. Y.

Original application July 29, 1950, Serial No. 176,741.

Divided and this application November 30, 1953, Serial 11 Claims. (Cl. 101-336) This invention relates to ribbon feed mechanism for 15 printing apparatus, such as in calculating and similar machines.

This application is a division of my application Ser.

No. 176,741 filed July 29, 1950 for Calculating Machine.

An object of the present invention is to provide a novelly constructed printing platen assembly with a traveling ribbon and novel reversing means for the latter, said assembly being adapted for operative connection to a calcuthe purpose of illustration only and are not intended as a definition of the limits of the invention.

In the drawings, wherein like reference characters refer to like parts throughout the several views,

Fig. 1 is a side elevational view of a paper and ribbon feed unit or printing platen assembly embodying one form of the invention;

Fig. 2 is a vertical side sectional view of the unit shown in Fig. 1, the section being taken substantially on line 47--47 of Fig. 6;

Fig. 3 is a detail side elevational view, partly in sec tion, of a portion of the ribbon feed mechanism;

Fig. 4 is a fragmentary front elevational view of said 2,821,918 Patented Feb. 4, 1958 "ice is a ratchet pawl 540 that is biased by a spring 541 toward operative engagement with ratchet wheel 534. The lower edge of pawl 540 has a shoulder 542 adapted to engage a pin or stud 543 on frame plate 530 to effect counterclockwise movement of the pawl and, hence, disengagement thereof from wheel 534 at the end of the forward movement of the pawl. The platen 2.72 is thus freed for rotary movement in either direction by handles 544, 545 on the ends of the platen shaft, but such movement is yieldably resisted by an indexing arm assembly comprising a pivoted arm 546 and a roller 547 mounted thereon and held in engagement with ratchet wheel 534 by a spring 548. The lower end 549 of arm 546 extends into the path of lever 536 for engagement thereby at the very end of the rearward stroke of said lever. A counterclockwise force or torque is thus applied to arm 546 by lever 536 to firmly press roller 547 into engagement with ratchet wheel 534 and hold platen 272 firmly against movement when the type quadrants 218, 250 strike the same.

Thus. on each operating stroke of link 537, the lower end of arm 536 and pawl 540 are moved to the right or toward the rear. Pawl 540, as it moves away from pin 543, is pivoted by spring 541 into engagement with ratchet 5 wheel 534 and lever 536 presses against the lower end unit, on a reduced scale, as viewed from the left in Figs.

l and 2; and

Figs. 5 and 6 are complementary rear elevational views, partly in section and with the paper supply roll removed, Fig. 5 showing elements illustrated in Fig. 1 and Fig. 6 showing elements illustrated in Fig. 2; and

Fig. 7 is a detail isometric view of the ribbon feed and reversing mechanism on an enlarged scale, with parts broken away and with the right and left hand portions broken apart near a central vertical plane and separated in the interest of clarity.

The single embodiment of the inventions illustrated in the accompanying drawings, by way of example, is in the form of a platen assembly embodying novel means for feeding an inked ribbon and for locking the platen against movement during the printing operation. In the illustrated embodiment, said assembly comprises a frame consisting primarily of side plates 530 and 531, a front end plate 532 and a bottom plate 533, all suitably rigid-' 1y secured together by screws or the like. The shaft of a journalled in side plates 530, 531 and has a ratchet wheel 534 mounted thereon for rotation therewith.

Pivotally mounted on the hub of ratchet wheel 534 is a pawl carrier 536 that extends downwardly and pivotalplaten 272 having a rubber or other suitable surface is 6 1y connects with a link 537, the forward end of which extends through plate 532 and is pivotally connected to suitable known means for imparting limited reciprocating movement thereto. Pivoted on a stud 539 on lever 536 549 of arm 546 to urge roller 547 into firm engagement with said wheel. On the return stroke, pawl 540 is effective to index the platen one tooth of the ratchet and thereafter shoulder 542 thereon engages stud 543 to effect disengagement of the pawl from the ratchet wheel. This is repeated during each cycle of operation of the machine.

An inked ribbon 558 is indexed or fed from one spool 559 to another spool 560, the same being guided and supported to extend across the front face of platen 272 by a vertically movable ribbon guide plate 561. Each spool 559, 560 is removably mounted on the outer end of one of two coaxial shafts 562, 562 for rotation therewith, the driving connections shown comprising radially slotted washers 563 staked on the shafts for cooperation with lugs 564 on the spools. A spring hook 566 on the spool coacts with a groove in the shaft to hold the spool against axial removal. Spool shafts 562 are journalled in coaxial bearings 567 supported by side plates 530 and 531 and have ratchet wheels 568, 568 mounted on the adjacent end portions thereof for rotation therewith.

Novel means are provided for controlling and actuating ratchet wheels 568 alternately to feed ribbon 558 back and forth between the right and left hand spools 559. 560. In the specific form herein shown, said means comprises a bail, the end arms 570, 571 of which are pivoted on bearings 567. Extending rearwardly from'the center of the cross-bar 572 of said bail and between ratchet wheels 568, 568 is an arm 573 that terminates in two upturned ears 574, 574. The bail 570--572 is biased in a counter-clockwise direction as viewed in Fig. 2' by suitable resilient means, such as coil spring 575. Upon pivotal movement of bail 57 0-572 about bearings 567 and hence, about the axis of shafts 562, the arm '573 moves in an are about said axis. Pivotally mounted on each ear 574 and adjacent a ratchet wheel 568 is an operating pawl 576 with a rearwardly extending nose 577. A lug 578 on the forward end of each operating pawl 576 extends laterally over the adjacent ratchet wheel 568 and beneath a locking pawl 579 pivoted on a rod 580 and also adapted to operatively engage a ratchet wheel 568. Each pawl 579 is biased clockwise (Fig. 2)- and toward a ratchet wheel 568 by a spring 581 connected to the cross-bar of bail 557 and each said pawl has a tab 582 extending laterally from the top edge thereofatr over the operating pawl 576 adjacent thereto,

The outer or rear end 583 of the center arm'573 on 3 bail 572 is bent downwardly and has a transversely-extending double-ended lever 584 pivotally mounted thereonby means of a headed pin 586. Upward movement =of the opposed endsof lever; or arm 584 is limited by pointed rearward projections-or stops 587 .of-ears 574 and-said iever is yieldably heldimone or, the otherof its limiting positions by a leaf springx588 rnounted on Irma-S73. For this purposethe rear end of the spring $88-has-acone-shaped projection .589 onthe lowersurface thereof for cooperationwith. aninverted V-shaped bump on the central upper edge'oflever 5.84, whereby said spring. functions as anover-centersnap action spring means in conjunction with lever I 584. The nose portions 577 of pawls 576 extend into the pathsof theendsof said lever-584 so that whenan end of :Ithelatteris-depressed, itwillpivot av pawl 57.6, 577 clockwiseto. thereby -.l-i-ft the lug 57-8 .on thepawlout of engagement' withits associated ratchet wheel andinto engagement :with -.a docking pawl .579tto lift the latter away from t-heratehet wheel. It-will thus be seen thatlever .fifikiseficctive-to holdeither set of pawls 576,, 579 in inoperative position while the other .set is biased to operative.positionebysa spring 581 and gravity.

.Actuation of pawlsets 576, 5.79 v is.-effeoted ithrough'ibail -.5.7.2, the lefthandcnd arm 5.71.of wtbich,JasvieWed-fmm the left inFig. 2, has a forked-extension (fig. .2) that ,projectsforwardly through framenplate532 for operative engagement -with-a .pin 590. :The lattenis vertically .actuatable by-zanyzsuitabletknown means (not shown) to .thereby:.lift. pin .590 andgpivot bail 572.:clockiwise. Clockwisemovement .of-bail .-572 ,.-:573 -is-.eifcctiv.e to acarry :operatingpawls 576.rear-wardly. Theppawl-576 which tis-ithen in operative position .will indexthe ratchet wheel .568 engaged byr'lug-5'Z8 .on the pawl-rand; hence, index said wheel and the ribbon spool connected therewith -.in .aclockwise-direction (Fig. 2). Thismovoment of .0ne:spool will-pull-the ribbonz558 from'ithe otherrsp'ool. Thus, during .successive cycles -of operation of :the ma- .chine, theribbon is indexed from one spool-.to-the other, the direction dependingupon whichset-iof pawls 576, 579 is in operative ,position. -.Pawls 57 9 :are-operative to; pre vent .reverse ..or counter-clockwise .movement vof rthe "ratchet wheels 568.

"Means-arerprovided for automatically. actuating ,lever 584 for reversingthe .direction .oftravel .of the. ribbon --55$ when .rnost-ofsit.has..be,en accumulatedson -ione.of I the aspools therefor. saidameansncomprises a pivotally .moun'ted Ushap ed (member 596 .having ver.tically; projecting endarmsi39l7-and '59.8. Thereristoner-ueshapedlmemher or rocker 596-.at each side-.ofithe platen ;frame. ('Figs. 5...and 6). Feeler.arm.5.98 is biased by.a;'.spring .599-into engagement with .the surface;of...the.ribbon.in one oththe spools-"559,560. Arml597.is mounted to movezintozthe ,path of .the adjacentteniof lever..584=:-when the-iri'ohon .on the spoolx.associated.ltherewith is substantially-idepleted and said lever :is moved .forwardly andwdownwardly' by pivotal movement-of: bail; armr573,.583. .ilhus, .as the 1ibbon .is .fed .OHiO'OIlGzSPOOlZbY .theoperationof .one set of.;pawls;.576, 57.9,,..the .upperendaof arm 598 therein moves .toward the rear andrcarrieszits,associated am. 597. with .it. andout of the gpathtof-lever .584. When the ribbon .on the other aspoolahas been;.depleted IO-:3 .zpredetermined minimum, .uarm 597 tof -.the .rocker .59 6 associated with. saidother wilLhavebeenmoved forwardly by .spring.599. into .the,path.of.- lever 584 forengagement Aby .the depressed.end.of-.said.lever during an.:indexin g stroke, i. .e. .during..downward..movement of the. lever with arm 573, L583. QSuch .engagement -will .cause the :lever 58 4 to pivot to. its others limiting, position under :control ofyspringl'fisll. ilhegpartstwillnthus be rendered roperative' to pull.the.ribbon.back.toltheempty spooLdur- .succes'sive operating cycles. of .the machine. .When :lithis tspoolfills tup .the control-lever.584.iS.-.again-=actuated by the other .lnernber .597 to; again reverse the .direction .or ribbonieedxinthe same manner. 'In the drawingsythe left end of lever 584 (Fig. 6) is in depressed position so that the parts are operative to feed ribbon from the left spool (Fig. 5) to the right spool (Fig. 6). This operation will be reversed when arm 597 of the left rocker 596 (Figs. 5 and 6) moves forwardly and below the depressed end of said lever 584 to cause the latter to flip to its other position as it moves bodily downward with the rear end of bail arm 573 when the latter is actuated by bail 571, 572.

There is thus provided an extremely compact and versatile machine wherein a relative small number of parts have beenassemblediinnovel combinations which function in novelcombination with each other. The various elements of the machine are designed and assembled with a view to facilitating assembly as well as inspection and repair of the machine. The parts of the machine may be readily and inexpensively manufactured and assembled by known manufacturing processes.

Although only a. single embodiment of the invention has been illustrated and described, it is to be expressly understood that the invention is not limited thereto but that various changes,particularly in the design and arrangement of the parts shown, may be made without departing from the spirit .and scope ..of. .th e invention as it will now be understood bythoseslgilledin the art.

What is claimed is:

1 ,In apparatus .ofthe class described, a pair of coaxial spools .each mountedon one of two rotatable shafts, -a ribboneonnected to said spools,;and means for selectively actuatingrsaid shafts-and thespools thereon to wind said ribbon onto .theactuated spool, said actuating means comprising an armextending transversely of said shafts in ra i lly .spaced:rlationdhereto .and pivoted. for angular movement: about .,the. ,aXi s=,of said shafts, said arm being biased in one direction b.y;resilient,rneans,-.a ratchet wheel mounted. onone .of. said. shafts, a ratchet wheel ,mounted on the other ofsaidshafts an operatingpawl mounted on saidarmand biasedtoward operativetengagement with one of saidsratchet wheels and-another :operating pawl mounted on said arm and biased toward operative engagement with the other-of; said ratchet wheels, means for selectivelyholdingone ortheother of said operating pawls out of engagement with its associated ratchet wheel, and

.means forsuccessivelyactuating said ,pawl carrying arm and said pawlsinan ,arc.about the .axis .of said shafts againstthe .efforts'ofsaid .-re$ilient mcansto ,thereby index the=wheelwhich.is-thenoperatively engaged by, asaid pawl.

2. Apparatus as defined in claim 1 wherein said means for holding oneorthe othenof said operating pawls out .of .operative. engagement .with its ratchet wheel comprises :a double ended'levenrnounted on said 'pawLcarrying arm for pivotal movementabout anaxis extending transverse- .lyto the.axis of said operating .pawls,.and wherein said operating pawls haveextensionsinthepaths of 'theop- ,posite. ends of said levenwhereby one of-said pawls is held inoperativewhengthedeveris in one position and theother said pawl is held inoperative whenthe leveris in another position.

.3. Apparatusas defined inpclaim 2 comprising stops on .saidmtm.and..engageable -by,opposite ends of said lever .-for;limiting the,pivota1'movement. ofsaid lever in both directions.

-4. Apparatuses defined inclaim 3 comprising overcenter snap-actionqspring,means-for yieldably holding said lever in its; limitingpositions.

5. Appanatusas;defined.inclaim 4 comprisingmeans tions to the otherfon reversing the direction of movement .of the ribbon between the spools.

-6. :Apparatusas defined in claiml comprising a spring biased locking pawlassociated witheachratchet wheel and. movable.todnoperative.position by. the operating pawl associated with the same, ratchet .wheeLwhen said operat- ;1ng..pawl.is moved toinoperative position, said locking pawls being operative to prevent reverse movement of said ratchet wheels. 7

7. Apparatus as defined in claim 4 comprising pivoted control means for said lever including a part engageable with the ribbon on a said spool and a part movable into the path of movement of one end of said lever to efiect actuation of the latter from one to the other of its limiting positions when the ribbon roll on said spool attains a predetermined diameter.

8. In apparatus of the class described, a frame, a pair of coaxial shafts rotatably mounted in said frame, a spool mounted on each of said shafts for rotation therewith, a ribbon having its ends connected to said spools, and means for selectively actuating said shafts and the spools thereon to wind said ribbon onto the spool which is thus selectively actuated, said actuating means comprising an arm extending transversely of said shaft in radially spaced relation thereto and pivoted for bodily angular movement in an are having its center at the axis of said shafts, said arm being biased in one direction of movement by resilient means, a ratchet Wheel mounted on each of said shafts for rotation therewith, and a pair of operating pawls mounted on said arm, each said pawl being biased toward operative engagement with a said ratchet wheel, means for selectively holding one or the other of said operating pawls out of operative engagement with its ratchet wheel, and means including said resilient means for reciprocating said arm and operating pawls along said are to thereby index the ratchet wheel which is then operatively engaged by one of said pawls.

9. In apparatus of the class described, a pair of axially spaced spools mounted for rotation about a common axis, a ribbon connected to said spools to be wound back and forth from one to the other and means for selectively actuating said spools to wind said ribbon onto the spool which is so actuated, said actuating means comprising a ratchet wheel connected to each of said spools for rotation therewith, an arm extending transversely of said axis in radially spaced relation thereto between said ratchet wheels and being pivotally mounted to move in an arc of a circle containing said axis, said arm being biased in one direction by resilient means, and a pair of operating pawls mounted on said arm, one of said pawls being biased toward operative engagement with one of said ratchet wheels and the other of said pawls being biased toward operative engagement with the other of said ratchet wheels, means for holding one or the other of said operating pawls out of engagement with its ratchet wheel, and means for reciprocating said arm and said pawls in said arc to thereby index the ratchet wheel which is then operatively engaged by one of said pawls.

10. Apparatus as defined in claim 9 comprising control means responsive to the portion of the ribbon wound on one or the other of said spools and operative to effect actuation of said holding means to move one of said operating pawls out of operative engagement with its ratchet wheel and permit movement of the other of said operating pawls into operative engagement with its ratchet wheel for reversing the direction of movement of the ribbon between the spools.

11. Apparatus as defined in claim 9 comprising two coaxial rotatable shafts having said spools secured to the remote end portions thereof and said ratchet wheels secured to the adjacent end portions thereof for rotation therewith.

References Cited in the file of this patent UNITED STATES PATENTS 1,811,359 Kern June 23, 1931 2,031,860 Shipley Feb. 25, 1936 2,100,027 Paris Nov. 23, 1937 2,187,200 Green Jan. 16, 1940 2,297,961 Hughes Oct. 6, 1942 2,335,679 Kennedy Nov. 30, 1943 2,592,706 Julius Apr. 15, 1952 

